Research in Developmental Disabilities 35 (2014) 1310–1316
Contents lists available at ScienceDirect
Research in Developmental Disabilities
Underlying mechanisms of writing difficulties among children
with Neurofibromatosis type 1
Yafit Gilboa a,*, Naomi Josman a, Aviva Fattal-Valevski b,
Hagit Toledano-Alhadef b, Sara Rosenblum a
a
Department of Occupational Therapy, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa 31905, Israel
Pediatric Neurology Unit and the Gilbert Israeli Neurofibromatosis Center (GINFC), Dana Children’s Hospital, Tel Aviv Sourasky Medical
Center, 6 Weizmann Street, Tel Aviv 64239, Israel
b
A R T I C L E I N F O
A B S T R A C T
Article history:
Received 15 January 2014
Received in revised form 9 March 2014
Accepted 9 March 2014
Available online
Writing is a complex activity in which lower-level perceptual-motor processes and higherlevel cognitive processes continuously interact. Preliminary evidence suggests that
writing difficulties are common to children with Neurofibromatosis type 1 (NF1). The aim
of this study was to compare the performance of children with and without NF1 in lower
(visual perception, motor coordination and visual-motor integration) and higher processes
(verbal and performance intelligence, visual spatial organization and visual memory)
required for intact writing; and to identify the components that predict the written
product’s spatial arrangement and content among children with NF1. Thirty children with
NF1 (ages 8–16) and 30 typically developing children matched by gender and age were
tested, using standardized assessments. Children with NF1 had a significantly inferior
performance in comparison to control children, on all tests that measured lower and
higher level processes. The cognitive planning skill was found as a predictor of the written
product’s spatial arrangement. The verbal intelligence predicted the written content level.
Results suggest that high level processes underlie the poor quality of writing product in
children with NF1. Treatment approaches for children with NF1 must include detailed
assessments of cognitive planning and language skills.
ß 2014 Elsevier Ltd. All rights reserved.
Keywords:
Neurofibromatosis type 1
Writing
Underling mechanisms
Cognitive planning
Language skills
1. Introduction
Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder that affects multiple systems in the human body,
including the peripheral and central nervous systems (Lehtonen, Howie, Trump, & Huson, 2013) with an approximate incidence
of 1 in 3000. There is a broad spectrum of phenotypic expression in individuals with NF1 that is characterized by café-au-lait
spots, multiple neurofibromas, optic gliomas and bone deformities. Moreover, cognitive impairment, learning disabilities and
behavioral problems are the most common complications in childhood (Braddock, Kapp-Simon, & Stein, 2011).
Studies have shown that individuals with NF1 have cognitive and perceptual deficits in both language and visuospatial
domains. However, visual perception impairment has long been considered a hallmark feature of the disorder with the
* Corresponding author. Tel.: +972 52 3362230; fax: +972 3 9364367.
E-mail addresses: yafitlaytman@yahoo.com, yafitgilboa@yahoo.com (Y. Gilboa), naomij@research.haifa.ac.il (N. Josman), afatal@post.tau.ac.il
(A. Fattal-Valevski), drtoledano@gmail.com (H. Toledano-Alhadef), rosens@univ.haifa.ac.il (S. Rosenblum).
http://dx.doi.org/10.1016/j.ridd.2014.03.021
0891-4222/ß 2014 Elsevier Ltd. All rights reserved.
Y. Gilboa et al. / Research in Developmental Disabilities 35 (2014) 1310–1316
1311
Judgment of Line Orientation test most often cited as showing this deficit in NF1. Moreover, children with NF1 have motor
coordination and visual-motor integration difficulties (Levine, Materek, Abel, O’Donnell, & Cutting, 2006). The difficulties
with these skills in children with NF1 may interfere with writing competency (Gilboa, Josman, Fattal-Valevski, ToledanoAlhadef, & Rosenblum, 2010).
Writing is an important task learned during early school years and is indispensable for participation in school activities
(Bumin & Kavak, 2010). Two separate components of writing were identified: transcription processes skills (handwriting and
spelling) and composition (content and quality of writing) (Berninger, Nagy, & Beers, 2011). Proficient handwriting has been
considered a prerequisite for later academic achievement (Volman, van Schendel, & Jongmans, 2006) such as story writing,
reading, comprehension, and mathematics (Bumin & Kavak, 2010). Writing is a higher-order skill, demanding coordination
of multiple processes simultaneously (Kim, Otaiba, Sidler, & Gruelich, 2013). Recent advances in the understanding of
writing problems have identified components of the underlying mechanism (Cheng-Lai, Li-Tsang, Chan, & Lo, 2013;
Rosenblum, 2013). It was found that this complex skill requires adequate performance in visual-motor coordination, motor
planning, cognitive and perceptual skills, language and tactile and kinesthetic sensitivities (Bumin & Kavak, 2010; Shen, Lee,
& Chen, 2012). Since writing involves the interaction of several cognitive and motor processes, it is highly sensitive to
neurological disturbances (Kushki, Schwellnus, Ilyas, & Chau, 2011).
Research about writing among children with NF1 is relatively scarce. Our previous study was the first to describe the
handwriting performance among children with NF1 in comparison to children with Typical Development (TD) (Gilboa et al.,
2010). The study used outcome measures to evaluate both the handwriting process (the mechanical aspects of writing tasks)
and two aspects of the written product (legibility and content). The handwriting legibility was evaluated by administering
the Hebrew Handwriting Evaluation (HHE) (Erez & Parush, 1999) and the product’s content was assessed with the Six-Trait
Writing Method (Spandel, 2004).
The results of this study indicated that regarding the handwriting legibility, the performance of children with NF1 was
significantly poorer in comparison to TD in the spatial arrangement of their written product: the vertical alignment of letters,
the spacing of words and letters, and letter size (HHE variable). Furthermore, their performance was also significantly poorer
in the level of the content as was measured by the total score of the Six-Trait Writing Model in comparison to TDs (as can be
seen in Fig. 1) (Gilboa et al., 2010). Following those results, the unique profile of children with NF1 and the complexity of
writing, further questions regarding the factors affecting writing skill among children with NF1 were raised.
According to Volman et al. (2006), the components which are required for the writing production were divided into
lower-level perceptual-motor processes and higher-level cognitive processes that continuously interact. Lower level
perceptual motor processes in writing consist of perception of either visual or auditory information, fine motor coordination and
visual-motor integration. The higher-level cognitive processes involved in writing include cognitive planning or working
memory and more specific language processes (Volman et al., 2006).
Evidence is accumulating that the writing legibility which was described in Volman’s theory, also has an important role in
written composition and implies the written content (Medwell & David, 2014). The current research has been enlarged Volman’s
theory beyond the legibility including the written composition quality of the content. Hence, the aim of the present study is to
identify the underline factors that may possibly explain the writing difficulties among children with NF1 and matched controls.
The following research assumptions were addressed: (A) there would be significant differences between children with
and without NF1 regarding (1) the lower level processes (i.e., visual perception, motor coordination and visual-motor
integration); and (2) the higher level process (verbal and performance intelligence, visual-spatial organization and visual
[(Fig._1)TD$IG]
Control
17.70±
NF1
20
3.15
13.93±
18
16
3.55
9.00±
2.75
14
7.86±
1.52
12
10
8
6
4
2
0
The Six-Trait Wring Model
HHE
Fig. 1. Differences between the groups for the spatial arrangement and the level of content. Note: Six Trait ! score indicates good performance. HHE ! score
indicates poor performance.
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Y. Gilboa et al. / Research in Developmental Disabilities 35 (2014) 1310–1316
memory) components; and (B) the above-mentioned components would interact and predict the writing product (spatial
arrangement and content) in children with NF1.
2. Methods
2.1. Participants
The study group consisted of 30 children diagnosed with NF1 (9 males, 21 females; mean age 12 years 3 months, 2 years
6 months; range 8–16 years 8 months). Medical notes of all patients in the research group were reviewed to confirm the diagnosis
of NF1 using National Institutes of Health Diagnostic Criteria (NIH, 1988). Exclusion criteria: patients without confirmed NF1, such
as sporadic cases with café-au lait patches but no other signs, and attending special education services for learning disabilities,
children with brain tumors, epilepsy, hydrocephalus, previous exposure to chemotherapy or radiation, a prior neurosurgical
procedure or a previous diagnosis of a Pervasive Developmental Disorder.
The control group consisted of 30 children, learning in regular schools matched to the study group by gender and age (9
males, 21 females; mean age 12 years 4 months, 2 years 5 months; range 8 years 5 months to 16 years 4 months). Mean IQ
score of the NF1 group (98.96 12.77) was significantly lower compared to the control group (107.19 12.08) (t = 2.47, p < .05).
2.2. Instruments
2.2.1. Outcome measures: written composition
2.2.1.1. The Hebrew Handwriting Evaluation (HHE). The Hebrew Handwriting Evaluation (HHE) (Erez & Parush, 1999) was
used to examine the legibility of the written text as determined according to detailed and precise criteria. Specifically, the
spatial arrangement of the writing product subtest was chosen since children with NF1 showed difficulties in this outcome
measure (Gilboa et al., 2010). The spatial arrangement criteria include the vertical alignment of letters (including the
extensions of letters above and below the lines), the spacing of words and letters (whether too wide or overlapping), and
letter size. The minimum score for spatial arrangement is 6, and the maximum score is 24. A low score indicates good
performance, and a high score indicates poor performance.
The inter-rater reliability of the HHE is r = .75–.79; p < .001. Construct validity of the HHE has been established by
demonstrating 12 statistically significant differences between the performance of children with proficient and poor
handwriting (Dvash, Levi, & Traub, 1995).
2.2.1.2. The Six-Trait Writing Model. The Six-Trait Writing Model (Spandel, 2004) was used to judge the written content
quality. The model, consisting of six broad writing dimensions, was used to judge the quality of the participants’ written
products: ideas (details, development, focus), organization (internal structure), voice (tone, style, purpose, and audience),
word choice (precise language and phrasing), sentence fluency (correctness, rhythm, and cadence), and conventions
(mechanical correctness). Each of the dimensions was scored by a numerical value of 1–5 where 1, a score of 1 would indicate
poor performance and a score of 5 would indicate strength in a given area. Total score was obtained by summarizing the
scores of the six dimensions. The composition was on a given school-topic.
Inter-rater reliability using Cohen’s Kappa coefficient was between .91 and .99 (Kozlow & Bellamy, 2005). Test–retest
reliability was calculated for 201 students who completed a second Six Traits sample, exact agreement (35–40%). Validity
data: The correlations of the different scales of the six traits with a standardized, norm-referenced achievement test
(Stanford-9) standard scores were .17–.43 (Gansle, Noell, Resetar, VanDerHeyden, & Williams, 2006).
2.2.2. Lower level processes predictors
2.2.2.1. Judgment of Line Orientation test (JLO). Judgment of Line Orientation test (JLO) (Benton, Varney, & Hamsher, 1976)
was used to examine differences in visual perception. The task consisted of a fan of eleven numbered lines displayed at the
bottom of the page; above the fan there was a pair of lines. Participants needed to identify and say the numbers of the two
lines that were oriented in the same position, aloud. The test has a high test–retest reliability as well as good
neuropsychological construct validity for children from the age of 7 years (Frazen, 2000). The dependent variable for this task
was the total number of correctly identified targets out of 30.
2.2.2.2. The Beery–Buktenica test of Visual Motor Integration – the motor coordination subtest (MC). The Beery–Buktenica test of
Visual Motor Integration – the motor coordination subtest (MC) (Beery, Buktenica, & Beery, 2004) was used to examine fine
motor coordination. In this task, children use a pen to draw a trail within borderlines derived from the same geometric figures.
The number of responses without mistakes is scored and converted to standardized scores (mean 100, SD 15).
2.2.2.3. The Beery–Buktenica Test of Visual Motor Integration (VMI). (Beery et al., 2004) was used to examine visual-motor
integration. In this task children are asked to copy 24 geometric figures starting with simple figures and ending with more
complex figures. Raw scores were converted to standardized scores. The VMI is regarded as a valid test of visual-motor
integration (Asher, 2007). The VMI is scored and converted to standardized scores (mean 100, SD 15).
Y. Gilboa et al. / Research in Developmental Disabilities 35 (2014) 1310–1316
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2.2.3. Higher level processes predictors
2.2.3.1. The Wechsler Intelligence Scales for Children – Revised 95: Hebrew version (WISC-R95) (Wechsler, 1998)-vocabulary
subtest. The Wechsler Intelligence Scales for Children – Revised 95: Hebrew version (WISC-R95) (Wechsler, 1998)vocabulary subtest was used to estimate the verbal intelligence. The Vocabulary subtest of the Wechsler scales is the most
reliable measure of verbal ability from the verbal scale (Kendera, 2005). This test requires the subject to orally define
stimulus words presented by the examiner. The words become increasingly difficult as the test progresses. The subject
receives a zero, one, or two-point score for each item based on the quality of the definition. Standard scores (s-scores) were
calculated with a mean of 10 and SD of 3.
2.2.3.2. The Rey Complex Figure Test (RCF). The Rey Complex Figure Test (RCF) (Rey, 1941) was used to assess cognitive planning.
This is a constructional copying a figure test. Because of the complexity of the figure the RCF has been widely used as measure of
visuospatial organizational skill and general planning ability (Schouten, Hendriksen, & Aldenkamp, 2009). Performance was
calculated using the Meyers and Meyers point scoring system (score range: 0–36, with higher scores indicating better
performance) (Meyers & Meyers, 1995). This system assigns points based on the presence, placement and accuracy of 18 items
in the figure. Median inter-rater reliability was .94, test–retest correlation was .76, and correlations with other
neuropsychological tests showed that the RCF scores were indicators of visuospatial memory (Meyers & Meyers, 1995).
2.3. Procedure
The study was approved by the Ethics Review Committee of the Tel Aviv Sourasky Medical Center. All participants in the
study group were active patients in the Gilbert Israeli Neurofibromatosis Center (GINFC) at the Pediatric Neurology Unit of
the Dana Children’s Hospital at the Sourasky Medical Center in Tel Aviv, Israel. Potential participants were recruited during
routine clinic visits. All parents signed an informed consent for their children’s participation in the study and participants
provided their assent. The age- and gender- matched control children were recruited from local elementary and middle
schools using snowball sampling methodology (Atkinson & Flint, 2004).
Testing was completed in individual sessions with each participant. The total time for completion of all measures was
approximately 1 h. Participants completed testing in a quiet, distraction-free testing room within a pediatric clinic setting.
2.4. Statistical analysis
Statistical analyses were performed using SPSS software (version 14.0). The means + SD were calculated. A multivariate
analysis of covariance (MANCOVA), with group membership serving as the independent variable and age as the covariate,
was used to examine group differences across: (1) the lower level processes tests (JLO, MC and VMI); and (2) the higher level
processes tests (the Vocabulary subtest of the WISC-R95 and the RCF) and Pearson correlations were calculated in order to
explore for possible associations between the lower and the higher processes and the outcome measures. Furthermore,
stepwise linear regression analyses for the NF1 and control group separately were applied to identify the strongest
predictors of the handwriting product in terms of spatial arrangement (HHE) and the content level (The Six-Trait Writing
Model). The lower level processes (JLO, MC and VMI) and higher level processes (Vocabulary and RCF), were entered as
predictor variables. For all analyses, a significance level of p < .05 was chosen.
3. Results
There were no significant age differences between NF1 participants and control participants (t = 1.4, p = .72).
3.1. Hypothesis A: comparison of performance between groups
Hypothesis A1. Lower level processes. The MANCOVA analysis indicating significant differences between the groups
(F(1,53) = 4.47, p = .007). As shown in Table 1 all the tests that measure the lower level processes: JLO, MC and VMI where
the NF1 group performed significantly worse than the control group.
Hypothesis A2. Higher level processes. The MANCOVA analysis indicating significant differences between the groups
(F(1,47) = 10.77, p = .000). As shown in Table 1 all the tests that measure the higher level processes: (the Vocabulary subtest
of the WISC-R95 and the RCF) where the NF1 group performed significantly worse than the control group.
3.2. Hypothesis B: relationship between writing product scores and the lower and higher level tests scores
3.2.1. Correlation analysis between lower and higher variables and children’s handwriting outcome measures among children with
NF1 and TD
Pearson correlations between writing product outcome measures and the lower and higher levels processes for the NF1
group and control group are presented in Table 2. In both groups, the total score of The Six-Trait Writing Model was
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Table 1
Lower and higher level processes tests scores.
Test
Lower level processes
Visual perception – JLO
Motor coordination – MC
(Mean = 100, SD = 15)
Visual-motor integration – VMI
(Mean = 100, SD = 15)
Higher level processes
Verbal Intelligence – vocabulary subtest of the WISC-R95
(Mean = 10, SD = 3)
Cognitive planning – RCF
NF1
N = 30
Control
N = 30
F
20.06 (5.11)
83.70 (21.64)
24.06 (5.33)
103.93 (16.32)
8.50**
4.86**
86.93 (17.17)
101.90 (14.74)
9.01**
9.88 (2.38)
12.46 (2.96)
11.65**
24.06 (8.95)
31.05 (3.15)
16.22**
** Significant p value < .01.
Table 2
Correlation coefficients of written composition and measures of lower level processes, and higher level processes.
NF1
Spatial arrangement (HHE)
The Six-Trait Writing Model
Control
Spatial arrangement (HHE)
The Six-Trait Writing Model
JLO
MC
VMI
Vocabularya
RCF
.21
.24
.23
.11
.14
.26
.47*
.48*
.66**
.34
.09
.22
.05
.19
.05
.36*
.07
.57**
.07
.14
a
Vocabulary subtest of the WISC-R95.
* Correlation is significant at the .05 level (2-tailed).
** Correlation is significant at the .01 level (2-tailed).
significantly correlated with Verbal IQ. Only in the NF1 group, the spatial arrangement of the text was significantly correlated
with RCF and Verbal IQ. Furthermore, only at the control group the total score of The Six-Trait Writing Model was
significantly correlated with the VMI score.
3.2.2. Prediction of the writing product scores by the varied lower and higher level tests scores
Stepwise regression analyses were conducted for each group separately with the total score of The Six-Trait Writing Model
that represent content quality and the spatial arrangement of the written text (HHE) as dependent variables. The lower level
tests scores (JLO, MC and VMI), and the higher level tests scores (Verbal IQ and RCF) were entered as predictors.
In both groups poor level of writing content was predicted by low Verbal Intelligence (NF1: R2 = 23% p < .05, Control:
2
R = 32% p < .01). Only in the NF1 group, The RCF predicted (R2 = 43%, p = .00) of the spatial arrangement of the written text
(HHE). None of the lower level variables significantly predicted the spatial arrangement or the content of handwriting in the
NF1 or control group.
4. Discussion
The present study investigated the role of different processes that underlie the poor performance of writing in a group of
children with NF1 in comparison to TD using Volman’s et al. (2006) theory. This study is the first that we are aware of where
the sole focus was on examining the relationship between tests that were originally designed for identifying underlying
perceptual-motor deficits and the real-world performance behavior of writing in children with NF1.
As expected from our hypotheses, children with NF1 were significantly less proficient on all of the lower and the higher
skills processes tests compared to matched control children. These results duplicate the results of previous studies that
described deficits in lower perceptual-motor process among children with NF1. Deficits were documented in the areas of
visual perception, motor coordination and visual motor integration (Levine et al., 2006). Our findings are also in line with
other studies that described the higher cognitive level impairments found in children with NF1. Deficits were documented
on verbal intelligence, visual organization and visual memory (Lehtonen et al., 2013).
To differentiate the specific processes that contribute to the impaired spatial writing arrangement of children with NF1
correlations and regression analyses were conducted. Only in the NF1 group there were significant correlations between the
RCF, verbal intelligence and the spatial arrangement of the written text. Moreover, the regression revealed that the RCF was
the best and only significant predictor of the spatial arrangement of the written text in the research group. Previous
research’s results also reflect that cognitive planning in children with handwriting problems is less proficient compared to
typically developed children (Volman et al., 2006).
Y. Gilboa et al. / Research in Developmental Disabilities 35 (2014) 1310–1316
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Beside of cognitive planning, the RCF designed to assess visuospatial/visuoconstructional perception and visuomotor
integration (Kramer & Wells, 2004; Loughan, Perna, & Galbreath, 2014) (lower level processes). Due to the complexity
of the figure, completion of the RCF copy also requires significant attentional, organizational, and problem solving
abilities, which are aspects of executive functioning (EF) (Loughan et al., 2014; Watanabe et al., 2005). Executive
functioning reflects advanced mechanisms that comprise several components of high cognitive processes, and the
dysfunction of these abilities can cause impairments in planning, cognitive fluency, and judgment (Watanabe et al.,
2005). The current results are in line with several studies suggested the relationship between difficulties in EF and
prominent problems in writing performance (Rosenblum, 2013; Rosenblum, Aloni, & Josman, 2010; Rosenblum,
Margieh, & Engel-Yeger, 2013).
Sandler et al. (1992) derived empirically four subtypes of writing disorders thorough neurodevelopmental instrument.
These results suggest that children with NF1 can be classified by specific subtype of writing disorder that is related to
visuospatial deficits. The children’s writing in this group was characterized by poor legibility, untidiness of handwriting, and
disorganized spatial planning of the page (Sandler et al., 1992).
As far as we know there were no other reports about association between verbal intelligence and problems with spatial
arrangement. Therefore, whether the coexisting verbal intelligence and writing legibility problems are causally related to
each other or they are the result of a common underlying deficit require further investigation.
In both groups, children’s expressive vocabulary was related to children’s written composition. The poor content was also
predicted by a deficit in the linguistic wealth (vocabulary subtest). The current results are not surprising. Indeed, other
researchers also indicated that vocabulary would play a role in written composition (Kim et al., 2013). Because writing is a
late-acquired and complex skill, it may be a particularly sensitive index of language difficulties in children (Berninger, 2009;
Bishop & Clarkson, 2003). Evidence in support of this view was obtained in a study contrasting normally developing control
children aged from 7.5 to 13 years with children of the same age with specific speech-language impairments. Written
narratives were elicited from children depicting a simple story, and were analyzed for grammatical complexity and accuracy,
intelligibility, and semantic content. Most children with language impairments were poor at writing, with particularly
marked deficits on a measure of spelling and punctuation (Bishop & Clarkson, 2003).
The association between VMI and the level of content in the control group was documented earlier. Visual-motor
coordination which allows a writer to manually produce legible letters smoothly and accurately was found to be affecting
spelling, If letter formation is difficult, a child is forced to concentrate on the motor requirements for writing which leaves
less capacity for spelling and formulation of syntax and content (Maki, Voeten, Vauras, & Poskiparta, 2001).
Further research has to elucidate the specific role of language processes in children with NF1 and handwriting difficulties.
It is necessary to use instruments to measure more specific language processes that might interfere with the handwriting
quality of children with NF1. Because of the exclusion criteria, our sample consisted of a rather homogeny group of children
with NF1 Replication studies that include different subtypes of NF1 children (e.g., children with optic gliomas) are needed to
investigate whether the contribution of underlying mechanisms responsible for handwriting problems differ for such
subtypes. Future research should also elucidate underlying mechanisms of other functional problems and focus on
prevention and possibilities for remediation.
Study limitations and suggestions for further research: First, our sample consisted of a relatively small heterogenic group
of children with NF1. Thus replication studies that include different subtypes of NF1 children (e.g., children who are classified
as learning disabled, children diagnosed with ADHD, children with optic pathway gliomas) should be investigated to see
whether the contribution of underlying mechanisms responsible for handwriting problems, differ for such subtypes. Such
insight may generate new guidelines for handwriting intervention programs.
Second, most participants were girls, thus raising a question about the ability to generalize the results to boys.
Furthermore, the study was done in Hebrew, which involves non-continuous writing. More studies are required in order to
examine these results in other languages with continuous writing, such as English or Arabic.
5. Conclusions
The findings of this study add to our understanding of the specific underlying mechanism that influence writing outcome
of children with NF1. Based on the current study results, the problems in spatial arrangement of the written text of children
with NF1 seem to stem from a deficit in visuospatial cognitive planning while the causes for the poor level of content are
mainly deficits in language.
From a clinical perspective, the result of the current study may generate new guidelines for handwriting evaluation and
therapeutic targets among children with NF1. The writing should especially be evaluated for the product in terms of legibility
(special arrangement) and content that warrant further assessment and treatment in school to overcome handwriting
problems. As assessment of performance components is one aspect of a comprehensive writing assessment (Klein, Guiltner,
Sollereder, & Cui, 2011) the current study results strongly recommend the component’s skills such EF and especially
cognitive planning and organization as well as visuospatial/visuoconstructional perception, visuomotor integration and
language should also be fully evaluated in children with NF1 referred for therapy due to handwriting deficiency. These can be
useful in order to increase the academic participation of children with NF1 in the essential activity of writing as part of school
performance. This would present the first step toward developing a practical handwriting evaluation for the specific needs of
this population.
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